This Small Grants for Exploratory Research (SGER) award will take advantage of the ~10-year peak-flow to occur in April, 2008, in the Mississippi River to gather direct measurements of carbon and sediment flux. In particular, this rare event provides an ideal opportunity to answer the following questions: 1) How is organic carbon of varying sources transported and processed by rivers? and 2) How do flooding rivers accumulate and distribute sediments to adjacent wetlands? A two stage sampling program (ship-based and land-based) will be employed to sample the suspended load, total organic carbon, bulk organic carbon age spectra,nutrients, and hydrology of the river during the peak-flow event. Hydro-acoustic techniques will be used to determine the velocity structure of the river in flood. Short-lived, naturally occurring radioisotopes (e.g. 7Be) will be used in combination with x-radiographs and classical sedimentology methods to quantify recent deposition. Long cores will be collected to ultimately compare these rates to long-term sedimentation histories.
In light of the environmental destruction that occurred in the Mississippi River delta region in 2005, coupled with the region's vulnerability to current and future climate changes, this project tackles issues that are highly relevant to both society, to policy and decision makers, and to a broad spectrum of environmental and engineering scientists.
